The identity of X-ray radiographs of plastically deformed annealed and unannealed crystals indicates that elastic changes in the orientation of neighboring sections of a plastically deformed unannealed crystal play an insignificant role in the formation of tails on the radiographs. The investigation of the nature of rotation led to a detailed study of tails on X-ray radiographs, since the reorientation of individual sites in a deformed crystal is most reliably established by means of X-ray radiographs. From a crystal, whose lattice is distorted, X-rays with blurred and split spots are obtained, asterisms and bridges between bright spots appear.

Mica is an extensive group of minerals characterized by perfect {001} cleavage, i.e. the ability to easily split into very thin sheets with a flat surface parallel to the face of the third pinacoid. Muscovite and phlogopite have the most important industrial value. Mica have high electrical characteristics, incombustibility and great mechanical strength, they are also thermally and chemically stable, and are not very hygroscopic. Mica crystallize in a monoclinic system, approaching hexagonal . forms. Under the influence of mechanical effects mica deform, lose their properties and become unsuitable for industrial purposes, so, of course, the study of deformed mica is paid much attention.

The study of the mechanism of plastic deformation is a very important problem. The mechanism of plastic deformation is influenced by a number of factors. In the present work, an attempt has been made to establish the effect of strain rate on plastic deformation. Asbestos fibers were taken as the material under test. Asbestos fibers have bonds much stronger within the fiber than between the fibers. Hence, such a fiber approaches a one-dimensional chain. The study of the mechanism on such material is of undoubted interest.